Lathe attachment



Jan. 8, 1946. R A, LAvoTA 2,392,596

I LATHE ATTACHMENT 4 Sheets-Sheet l Filed Feb. 17, 1944 Janv 8, 1946. R.A. LAVOTA LATHE ATTACHMENT 4 Sheets-Sheet 2 Inventor Filed Feb. 1'7,1944 Jan. 8, 1946. R. A. LAVOTA 2,392,596

LATHE ATTACHMENT Filed Feb. 17, 1.944 4 Sheets-Sheet 3' ij InventorPatented Jan. 8, 1946 gases ge LAllH -A'DTAGIMENm wep e IevApplieationFeb uiey 17, 1944, Sei iaJ No. 522,835

c -ome et This invention relates to iath'e attachments, and pertiemaflyto "an "e-tt 'cmnenfi ife lame empieying a"conepsibie te 'r rf-tpre dinwoifkjhelq iittl'i ehiielifuhitofthe'laltheg tiqr'fel'l'thesl" 'ahciimore spe ci'fio objects and features ir vep'tion will fbeeome apparentthe fo'l deseriptio'n when considered. newt-gentrithe accompanyingdrawings, arid the iriiie 'ition consists in the not/e1 form,combiiitibii and'eitengeinefit b barts hereinafter Iifor juliy desezibfed, 'sh'o'wi1'in the accompanying dflii ihESiahd-lfimijd; "Iii the?df'aiiiihis', iwhereinjike "reference characters *1"aicate' corresponing ar s throughout iis ejiside elevetionel vie w pf a, lathe qui ed atafimnm m. C nst u d i ab-1 eaa wt fh i Si F men ion: j m 2 is; at p planv ewmhe 'r. e

Figiire If! -is gali (enlarged eleyational View of the forked atutmerivnm .m'pi yea to automatik n ranged fcez tiahlongitudinal 1 Qf Y-YtIieaQIiuStehIe'fewinging ar r eabe en i tembe o n. in

Figure 6 is an enla ged eigie elevationei yiew of. the, l eye r forminghart, ofvthe means for elevatm'g; tr ebiitmtitmeinber ofi Figiife 4 pqnwithdraiilal of the tap" from the 'w'orl; whereby saidafiiitifientfjrienibeifl will be moved Ofitofv the way. tdlfieif' riit.withdrawal of the threeqed, wot-1545mm eeth- 9 5isei e ifielethe Figutis an edge elevetiona view or x1e v'ice'shown in' Ei'giire 6; at-idFigure 8 15 an ema-rged fragmentq viewp rtly in "section eiid p'eiftlyin 'side e1evati;on, show ingeh end portion of the ai'm illustretefl-fihFig'iire 5 -ahd th'emour itirigtherefior; Refer rin'gi'h detail tothefliawingw-the-isresent in entip n 13* illustrated as appneaqm a tunet lathe of eon vemian r eons't 'ueti ninellifiifig a bed :5 nieuiiteauppertm i'egs; limh'd he" m sbaeed outer and inneiitearings 1-and a egon end in which is jour iialed the indie-9 mvi'zjg driving piilleys In;u ual 'dk -umt -l I es provided ongthe spin'd1e -at the mhei= side-m heinner bearin 8? 'mie mm;homer-often tithe illusti'at'ed e'o'hs'ists 01a, turretgrzwh ehiea 1 ateti by 'cnventionai meehan'is'm to -feed it' twere aiid away hem the chuck unit H a n'gi thereby feed the tool-gm thework and withdrew said from the work The present ihventioii'-or efitechment is essentially designed for useimconfneetiqxi witha lathe employingia collapsible ta p i threading work-placed in the :chuc-k me l1, sa'mtab I 3 being mounted in the tool helderfor turret I2 end being of thetyp embodying-ah externally fiahged actuator 44 which is shi-ftel to theright of Figure- 1 for coua'psmg e; ta end ermittmg its remdyale fromthe work et the 'eomplet ii-io'f; eaLoh threading operation;- andfwh-ic-h -is sh v table tothe leftof-Fig'lire 1 to expehdtheta-p andeondition it for the next supeeedirjig threading 01 talpping operetioi rThe elements finjd eontrii'eg tion thfis fall described arecofive'ntional find Welt known in the ai t, and the te'p i o'f thetypeshovin inthe' U'. s. remit to G HQBurIey- N05 8043 928;- the element22,23 of the patent cerre'spontiin'g to the actuator. 14. herein.Axiothe'r tap suitable Io? use: in i this: invention is available on thema rkt and is knownas the Murcheyself-openi ng e'nd closingitanu r Inaccordance with the present invention, -2aln abutment, generallyindicated at I'5,{is 'irroiitite'd; upon :the bed 5 inposition-tobra-engaged b'y' the actuator" 114; :so as to shift the.latter to the leit oft-Figure 1 and tl cause-expansion-ofthe t'aip' -3when the 17001v hblde'i or -turi'e'td 2 11375 Ii'-i6d'-t0= completelywithdrew-the ta-pl'3 from-the Work? As. shown this abiitmentt'consistsof a :base plate I6..havin g. an vundercut groov [1 in the bottomthereof to fitthe longitudinal "dovetaiiled r-if): I 8 provided on. thebed 5 of "thelathegmeens include ing a, gib -19 being. provided to.secure- Sthe base plate; :I 6, in, @the desired-.1 position:longituditietlyof gthje bed so; that thefwabiitment s! 5 171111 actuatethe tag ,1 3mm;- the propeiptime. In; otherwvoifiez.

the abutment I5 is adjustable longitudinally of the bed 5 so that itmaybe set and secured in proper position, and said abutment furtherincludes an upright plate 20 fixed on and rising from the base plate I6and bifurcated at its upper end, as at 2 I, so as to partially embracethe shank of tap I3 and project in the path of the adjacent flange ofactuator I4.

The present attachment further includes a vertically swinging arm 22which is adjustable in length and pivotallymounted at one end, as at 23,on a plate 24 fixed to the'cap 25 of lathe hearing 8. The arm 22 is thusmounted for vertical swingingmovement so as to project toward the tap I3and beyond the free end of chuck unit I I,

as shown clearly in Figures 1 and 2. As shown in Figure 5, the arm 22consists of telescopic secascasee q. 1 1' action of spring 31 so as toelevate arm 22 and thereby raise the abutment member 29 out of the wayto permit convenient removal of the work from the chuck unit II. Thearrangement is further such that as the tool holder or turret I2 is fedto the work, the lever 34 is permitted to swing under the influence ofspring 3'! in a direction to allow the arm 22 to lower for positioningthe abutment member 29 injthe path of the actuator I4 so thatthe latterwill be shifted to collapse the tap I3 upon completion of the threadingor tapping operation. As shown in Figures 1, 2, 6 and 7, the lever 34has a lateral ear 40 through which one end of rod 39 slidably tions, theouter one being pivoted at 23,'and the inner section 26 consisting of athreaded rod having a nut 21 threaded thereon at the outer end of theouter section. Also, the rod 26 is flattened at one side and is engagedat this side by a set screw 28 threaded through the outer section of.the arm 22, so that the rod 26 is restrained from rotation. Thus; byadjusting the nut 21, the inner section 26 of the arm 22 may be adjustedlongitudinally of said outer section of arm 22. The adjustment may besecured by tightening the set screw 28. Mounted onthe outer end of theinner arm section 26 is a bifurcated abutment member 29 which depends inposition to straddle the tap I3 and lie in the path of the actuator I4,so that when the tap has entered the work sufficiently to complet thethreading or' tapping operation, said abutment member 29 will haveengaged the adjacent flange of actuator I 4; and shifted the latter tothe right of Figure 1 to effect collapsing of the tap I3. This permitsthe with drawal of tap I3 when the tool holder or turret I2 issubsequently automatically withdrawn from the work by means of theautomatic mechanism of the lathe. Obviously, the adjustment of, the arm22 positions the abutment member'29 in the proper location according tothe depth of the work and the distance at which the tap I3 is adapted toenter the work for the particular threading operation being doneAsrshown, the abutment member 29 has an opening 30 at the top whichreceives the reduced outer end portion 3| of the arm section 26, a nut32 being threaded on thereduced end 3! of section 26 to secure the aabutment member 29 thereon. Attached to the plate 24 is an angularbracket 33Ihaving an arm depending at one side of the chuck unit' II towhich is pivoted a lever 34, as at 35. The lever 34 is pivotedintermediate its ends,' and has a laterally projecting'j'pin '36 at itsupper end extending transversely beneath the arm '22; A helical tensionspring 31 is attached at one end to plate 24 and atits other end to thelower arm of lever'34 so as to normally swing the latterto a positionwherein the arm 22 is permitted to lower to operative position withrespect to actuator I4 of tap I3," as shown" in Figure 1, it beingunderstood that the downward swinging movement of arm 22 is limited to'ahori-" zontal positioniby reason of the pivotalmount-: ing thereof. Thisis illustrated in Figure 8 wherein the arm 22 is arranged to abut theplate'24,

as at 38, when in its'downwardly swung horizontal position. A rod 39connects the lower arm of lever 34 with the tool holder or turret I2,the'arra'ngement being such that when said tool holder or. turret-ismoved to withdraw the tap I3 from the work, the lever34v is caused toswing against the the portion of the rod 39 betweenthe ear v4|} andvextends, said end of rod 39 being retained in the ear 40 by means of anut 4I threaded on the rod 39. A bracket 42 is flxed to one side of thetool holder or turret I2 and has the other end ofrod 39 extendedtherethrough, nuts 43 being threaded on this end of rod 39 and retainingthe rod 39connected to-thebracket 42'. Adjustment of nuts 43 can-be hadfor varying theflength of bracket 42 so that arm 22 will b permitted tocompletely lower when the tap is; fedto 5 the work and will be causedtomove upwardlya proper distance when the tapis withdrawn from the work- 1V From the foregoing description, it is believed that the constructionand operation, aslwell as the advantages of the fpresentinvention, willbe readily understood and appreciated -by those skilled the art. Upon.shifting of turret I2=to the right of Figure l to efiect complete with:-drawal of tap I3 from the work and the chuck unit I I in which the Workis held, the abutment I5 will have engaged the actuator. l4 and shiftedit to the left of said figure so as to causeexpansion of tap I3 andthereby to condition the latter for v the threading operation. When thisoccurs a pull is exerted on rod 39 to swing lever 34 andelevategarm 22so as to'rais'e abutment member 29 out of the way and permit readyinsertion of work in the chuck unit I I'. The feed mechanism f the lathethen shifts the (turret I2 so as to fee? ihe tap I3 to the Work in thechuck unit 'I Ljhelflby movin rod 39and swinging lever 34- -so;as topermit arm 2 2' and abutment member 29';to;lower., When the ta hascompleted-the threadingoperation, the abutment 29 will ha ve engaged theac tuator I3 and shifted the latterso astocollapse the tap I3, therebypermitting withdrawal ,0f:the

latterfrom the work upon the subseduentiriovee ment of turret. I2 towithdraw the an; I 3 from tlie work. When the turret 7 i2 is mus movedtoitwithdraw" the tap from'the work, a pullfis exerted-on rod 39 st) asto swin'gllever' 34 and elevate armizz and abutment Mythere-by raisingthe ab utrnentl29 I and scope of the invention as claimed.

to an out-of-the-way position so that the work may be readily removedfrom the chuckunit' II. This cycle of operation is; repeated as 8 as thethreading ofjwork is continued. I

While I have shown and described'lhereina preierred embodiment of theinvention, itjwillof 7 course be understood thatmino'r changesin'details of construction illustrated and described maybe made suchasfairly fallwithin the spirit.

What I claim aSLnew;is: I V v 1. In combination withalathehaving'apowerdriven rotary chuck" unit and provided" with a tool holder mounting a.collapsible tap having an actuator. and fed W d irqm t e; shudsunit for.entering the tap intofa-nd withdrawing the tap from the work, anabutment mounted on the bed of the lathe and disposed in the path of thetap actuator for expanding the tap to operative condition uponwithdrawal of the tap from the work, a second abutment mounted on theinner chuck shaft bearing of the lathe and including a verticallymovable abutment member positionable in lowered position for engagingthe actuator and collapsing the tap upon completion of the tappingoperation, and means operatively connecting the tool holder and thesecondnamed abutment member for permitting the latter to lower tooperative position as the tap enters the work and for elevating saidsecond-named abutment member to an out-of-the-way position uponcompletion of the tapping operation.

2. In combination with a lathe having a rotary power-driven chuck unitand provided with a tool holder mounting a collapsible tap having anexternal actuator, said tool holder being fed to enter the tap in thework and then withdraw the tap from the work, an abutment fixed on thebed of the lathe in position to engage and shift the actuator forexpanding the tap to operative condition upon withdrawal of the tap fromthe work, a vertically movable arm mounted on a chuck shaft bearing ofthe lathe and carrying a second abutment member, a pivoted leveroperable for elevating said arm and the abutment member carried thereby,and means operatively connecting said lever with said tool holderwhereby said arm and its abutment member are elevated to anout-of-the-way position upon withdrawal of the tap from the work, so asto permit ready removal of the work from the chuck unit.

3. In combination with a lathe having a rotary power-driven chuck unitand provided with a tool holder mounting a collapsible tap having anexternal actuator, said tool holder being fed to enter the tap in thework and then withdraw the tap from the work, an abutment fixed on thebed of the lathe in position to engage and shift the actuator forexpanding the tap to operative condition upon withdrawal of the tap fromthe work, a vertically movable arm mounted on a chuck shaft bearing ofthe lathe and carrying a second abutment member, a pivoted leveroperable for elevating said arm and the abutment member carried thereby,and means operatively connecting said lever with said tool holderwhereby said arm and its abutment member are elevated to anout-of-the-way position upon with wardly to permit lowering of the armand operative positioning of the second abutment member when the tap isfed to the work, said second abutment member being positioned whenlowered to operative position so as to shift the actuator and collapsethe tap upon completion of the threading operation.

4. In combination with a lathe having a rotary power-driven chuck unitand provided with a tool holder mounting a collapsible tap having anexternal actuator, said tool holder being fed to enter the tap in thework and then withdraw the tap from the work, an abutment fixed on thebed of the lathe in position to engage and shift the actuator forexpanding the tap to operative condition upon withdrawal of the tap fromthe work, a vertically movable arm mounted on a chuck shaft bearing ofthe lathe and carrying a second abutment member, a pivotedlever operablefor elevating said arm and the abutment member carried thereby, andmeans operatively connecting said lever with said tool holder wherebysaid arm and its abutment member are elevated to an out-of-the-wayposition upon withdrawal of the tap from the work, so as to permit readyremoval of the work from the chuck unit, and means to adjust the secondabutment member in a direction parallel with the movement of the tap,whereby the time of collapsing the tap may be adjusted as predeterminedby the depth at which the tap is adapted to enter the work to completethe threading operation.

5. In combination with a lathe having a powerdriven rotary chuck unitand provided with a tool holder mounting a collapsible tap having anactuator and fed to and from the chuck unit for entering the tap intoand withdrawing the tap from the work, an abutment mounted on the latheand disposed in the path of the tap actulater for expanding the tap tooperative condidrawal of the tap from the work, so as to permit I tionupon withdrawal of the tap from the work, a second abutment mounted onthe lathe and including a vertically movable abutment memberpositionable in lowered operative position for engaging the tap actuatorand collapsing the tap upon completion of the tapping operation, andmeans operatively connecting the tool holder and the second-namedabutment member for permitting the latter to lower to operative positionas the tap enters the work and for elevating said second-named abutmentmember to an out-ofthe-way inoperative position upon completion of thetapping operation.

' RUDOLPH A. LAVOTA.

